Tropical Wave Thread

[Iceberg]

Just looking at the picture in the atlantic again, 4 active waves currently, with two (2 and 3), showing the most immediate promise, although not that much it has to be said.

Wave 2 has some good circulation but very little organised activity.

Wave 3 has the activity without the required circulation (quikscat indicated moderate 15-20Kt winds associated more with the tunderstorms that any Tropical storm activity).

These can change very quickly though.

Sorry I couldn't find a generic Wave thread.

[kold weather]

Thats a nice wave that is heading very close to South America, nice convection with some fairly cool cloudtops.

Too far south however and also too far east for development right now and really too early for systems to get going in June, I believe just one storm formed outside of the GOM/BOC/Caribbean sea in June. Even in the heart of summer its so close to land it'll start to take in dry air and smash right into land before long.

Wave 3 looks far less impressive though its in a better position, but shear looks too overwhelming in this regiion right now, even though its below the average for the time of year...not a good trend!

I'd watch the Yucatan Channel, area of tropical moisture is present there and while short lived there is fairly deep convection right now. i don't expect anything but it'll be good for the Se states if it decides to head the same way as Barry through the same weakness.

Anyay thanks for opening this thread, I'll just rename it Wave thread, might as well be the place where all talk about waves go, saves space!

(ps, is it the other way round, on your map 2=3 and 3=2?)

Edited June 4, 2007 by kold weather

[Iceberg]

Yep type 2 should be 3.

I completely agree not much promise in either. We have an active ITCZ it just needs to be further north.

[kold weather]

Right quick post- there is a new tropical wave I'm just watching a little closer right now, just about ready to head into the Caribbean right now. Recent flare-up in convection meaning the wave also had an area of deeper convection present with it. Currently the tropical wave is just to the east of the Lesser Antilles and is slowly heading westwards towards the Cairbbean.

Right now the wave is being sheatred rather badly and ther eis just aobut no chance of development till this comes down however it is coming into a much warmer then average Caribbean and so if the shear does ease down I certainly wouldn't rule out some sort of tropical development as heat content is more then high eonugh ion that region to support tropical. We will just have to wait and see though.

[kold weather]

Update to todays post, fairly major wave has just moved off from Africa about 12hrs ago, extremely well defined mid-level circulation, by far the best to come of Africa this season. Because of the temps further west any development is highly highly unlikely unless it does it right now, its relative low latitude is probably helping to sustain it very well right now because heat content is probably just about high enough. As it travels further westwards it decreases to such a point where convection will probably struggle to keep going and the main zone for development this early in the season is the Caribbean and the Gulf, its really the only -places bar the gulf stream that high enough content to support pure tropical cyclones right now and that wave will take a Long time to reach there and it'll be a real test of how persistent it is, still if it survives as a wave then it may have a shot another 10 days down the line in the Caribbean.

Sw Caribbean flaring like mad right now, tohugh its a hotspot for activity usually at this ime of year but may need t obe watched if it keeps going simply because its in a hotspot for June/July development.

Edited June 9, 2007 by kold weather

[summer blizzard]

Kold Weather, if the wave can survive past 40 degrees west, it should be able to reorginise better and develop, i think we will know the furture of this storm in 72 hours...

[Iceberg]

It does indeed look very good and has been upgraded to Invest 93l.

Models don't really take a liking and even GFDL kills it instantly, IMO this is more to do with it's location which the models don't really handle well, GFS keeps the system intact, but both GFS and METO have it ploughing straight west without any recurve north. The ITCZ might just be a little bit to far south for this to really take effect.

[kold weather]

It looks pretty decent this morning, though it is lacking a little deep convection its actual structure is still probably as good as yesterday and its still got a very evident MLC. Some moderately deep convection present on the northern side of the circulation. will have to keep any eye on it, if convection flares up again then it may well get upgraded to a tropical depression, esp if a closed low level circulation is found by sat. imagery.

It really shouldn't develop where it is now to be honest, for June cape Verde systems are amazingly rare (I'm not sure if there has ever been a tropical storm cape Verde system in June!) so its hardly surprising the models are so keen to kill it off. To its west is even less heat content which should mean even less deep convection should slowly come about and that could be a problem for any developing system and then there is always the risk of shear as it gains latitude, its low latitude has saved it from any sort of shear so far. Shear maps seem to indicate it has got a window of opportunity though to develop, probably for another 36hrs before conditions become unfavorable. I'd also watch out just in case this system tries to develop further west as well, I think providing it can keep a low latitude it has another shot at development once past 40-50W, depending on shear but heat content rises again as you get closer to the Caribbean.

All in all this system has a real shot at being TD3, long term chances are stacked right against it simply because its rare for cape Verde systems to get going in July, yet alone June. It reminds me a lot of the 05 hurricane season where hefty waves moved off Africa. Sure most didn't develop but these waves served as the seeds that became monsters such as Dennis, Emily, Katrina, Rita and others.

Edited June 10, 2007 by kold weather

[Mondy]

Probably end up being another Alberto....lol

[summer blizzard]

http://wxmaps.org/pix/hurpot.html#ATL

This is the latest heat content map, and as you can see, once past 50 West, it should have a chance to develop, if the storm survives another 96 hours, i will call for its development.

[kold weather]

The convection on the wave has nearly gone with deep convection not being able to sustain itself. Given the SST's over 10 degrees north are extremely marginal and also the heat content pretty quickly between 10-12N where it is right now and the warm water isn't deep enough yet to sustain tropical cyclones in that part of the world, hence the lack of them.

Still it has a very nice curvature and clearly has a strong mid-low level circulation with the system though the convection has got to increase for it to have a shot at keeping that circulation for more then 12-24hrs, with no convection and a very slack gradient in the Atlantic it could very easily unwind again. There are a few cells to the south of the wave on the ITCZ and a few on the northern side of the wave but its not going to be enough to sustain the system I reckon. Current track takes it just south of WNW out in the Atlantic and should it pick up any more latitude then it has right now then it'll be very unlikely to survive. shame because it looked decent this morning!

By the way, just for your information the heat content is now rapidly increasing in the tropical part of the Atlantic, another 4 weeks and this wave would have had a real shot at keeping going given the latitude its at:

http://www.aoml.noaa.gov/phod/dataphod1/wo...W/2007157at.jpg

[Mondy]

So a fish-spinner then?!

[summer blizzard]

While it has lost convection, it does appear to have a circulation, so if it still has a circulation in 3-4 days when it reaches 50 west, i believe that we will see development from this system and that it may pose a problem for Florida.

[Somerset Squall]

While it has lost convection, it does appear to have a circulation, so if it still has a circulation in 3-4 days when it reaches 50 west, i believe that we will see development from this system and that it may pose a problem for Florida.

Quote from NHC:

A LARGE TROPICAL WAVE IS LOCATED S OF THE CAPE VERDE ISLANDS

ALONG 25W/26W S OF 14N. THE WAVE IS MOVING WEST NEAR 25 KT. A

WEAK 1012 SFC LOW IS ALONG THE WAVE AXIS NEAR 10N. ASSOCIATED

SHOWER AND THUNDERSTORM ACTIVITY HAS DIMINISHED. UNFAVORABLE

UPPER-LEVEL WINDS...COOLER WATER TEMPERATURES...AFRICAN

DUST...AND A FAST MOVEMENT WILL HAMPER FURTHER DEVELOPMENT.

Not looking good really for this wave. As KW said, if it goes on too long without convection (and it may well do due to the range of unfavourable conditions in the area) then the circulation will be lost.

[summer blizzard]

The wave has broken through 50W, however it appears that it has lost its circulation.

[kold weather]

Quite interesting developments over the last 24hrs, area i mentioned on the 9th of June has continued to be sustained though quite messy in nature its very close to the set-up we saw in Barry. Convection is fairly deep in places, as you'd expect given the high heat content that is already present over the region. The other thing that this system has is a broad circulation, however it is broad and not well organised but it is a LLC. Therefore if it can pull the convection into a better organized structure then it will almost certainly be given an invest today. Recon is also possible if the system carries on bursting with convection, because of its broad LLC and its possible eventual track will probably take it towards the USA.

In terms of development, sea surface temps and the heat content both look high enough for decent development. The factor that will make this harder is the upper low located near the Yucatan which is helping to inflict between 20-30kts of shear which is almost certainly why the LLC is so broad right now. IF the shear eases down then expect a more dominant center to develop inside the broad circulation.

i wouldn't like to say what chance it has of development, it could have a shot given the large convection present and the circulation already present gives it a better chance then some systems however shear may have to ease down a little first. However Barry developed in a very similar set-up and so it needs close watching indeed because it may develop into a hybrid system/tropical system. The best chance it has is if it can escape the shear. Given it has very little movement indeed there is a real chance it may be lucky enough to find a pocket of lower shear soon but that is in the air.

[summer blizzard]

http://www.goes.noaa.gov/GIFS/HUIR.JPG

I could be wrong, but i dont think that the wave has enougth lattitude.

If it turns out it does have enougth lattitude, then there are two factors against it...

1) Shear

2) Speed

In regards to speed, it does need to slow down, however i think that it may start to do so over the next 24 hours...

In regards to shear, that is more complicated, as far as i can tell, the wave is already under moderate to strong shear, but coping quite well in my opinion however shear will increase from now until saturday in my opinion however should the circulation survive and still be present on saturday, then the storm will be in the area of highest heat content in the Carribean and we could see development, unfortunately, because it will be developing fairly late, i cannot see it being more than a Tropical Storm.

Could somebody provide the link for shear and steering maps please????

Edited June 14, 2007 by summer blizzard

[summer blizzard]

A TROPICAL WAVE HAS BEEN ADJUSTED SLIGHTLY ALONG 31W S OF 13N

MOVING W NEAR 15 KT. THIS UPDATED PSN IS PLACED ALONG THE AXIS

OF AN INVERTED V-SHAPE SEEN ON SATELLITE IMAGERY. IN

ADDITION...A QSCAT PASS AROUND 8Z SHOWED SOME TURNING IN THE

FLOW ALONG THE SRN PORTION OF THE ANALYZED PSN AND AN

INCREASE IN THE WINDS BEHIND THE AXIS. SCATTERED SHOWERS AND

ISOLATED TSTMS ARE WITHIN 180 NM EITHER SIDE OF THE WAVE AXIS.

A WEAK TROPICAL WAVE IS IN THE ERN CARIBBEAN ALONG 66W S OF 16N

MOVING W NEAR 15 KT. THIS WAVE IS NO LONGER DISCERNIBLE IN

SATELLITE PICTURES OR SFC OBSERVATIONS AND LIES IN A REGION OF

VERY STABLE AIR TO THE W OF A LARGE UPPER LOW E OF THE LESSER

ANTILLES.

A LOW AMPLITUDE TROPICAL WAVE IS MOVING ACROSS THE SRN CARIBBEAN

ALONG 75W/76W MOVING W 10-15 KT. SIMILARLY TO THE WAVE IN THE E

CARIB...THIS ONE IS NOT RECOGNIZABLE IN CURRENT DATA. THEREFORE

THE PSN IS BASED ON CONTINUITY. A CLUSTER OF MODERATE CONVECTION

IS MOVING W OVER PANAMA AND WRN COLOMBIA...LIKELY ASSOCIATED

WITH THE ITCZ.

Kold Weather, does the wave at 66W still have a circulation??

[summer blizzard]

http://www.goes.noaa.gov/GIFS/HUIR.JPG

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 60W SOUTH OF 16N MOVING

WEST 15 KT. THIS TROPICAL WAVE ALSO HAS A SURGE OF DRY STABLE

AIR WITH AFRICAN DUST JUST E OF THE WAVE AXIS THAT EXTENDS E TO

30W MOVING W AT 15 KT. SCATTERED MODERATE CONVECTION IS OVER

THE WINDWARD ISLANDS FROM 12N-14N BETWEEN 58W-64W.

This is really the only wave with potential at the moment, though dry air is behind it, so convection is probably lop sided, given a low shear enviroment with very warm waters i would not be suprised to see development occur.

[Iceberg]

Still very little going on, a couple of weak and not very interesting Waves exist.

The main driver for the lack of activity seems to be the still very southerly ITCZ caused in part by the none migration of the Azores High yet ( and no summer for us to as a consequence).

The southerly ITCZ largely prevents any LLCC from occuring in any active waves, Convection is seemly being quashed by persistantly high pressure.

In essence it looks like when our summer starts so will the Hurricane season.

Oh hum......

[kold weather]

Yeah not much to note right now. Small Baroclinic low swirling off Florida which would have needed watching but its being sheared very badly right now and convection is all on the eastern side, and so I'll be very surprise df it does develop. The only thing to watch is it is heading south right now and there may be a small shot IF it can escape the shear but thats the big question.

[mettalfabrik]

LATEST DISCUSSION FROM NHC

THE ATLANTIC OCEAN...

THE LARGE CYCLONIC CIRCULATION PREVIOUSLY MENTIONED OVER THE

CENTRAL BAHAMAS IS FORECAST TO SLOWLY MOVE W TOWARDS SOUTH

FLORIDA HELPING TO GENERATE A FEW STRONG TSTMS THIS AFTERNOON

INTO EARLY THIS EVENING. AN UPPER RIDGE EXTENDS MAINLY N FROM

THE E CARIBBEAN INTO THE W ATLC BETWEEN 60W-70W. A BROAD

CYCLONIC CIRCULATION IS OVER THE CENTRAL ATLC NEAR 22N48W WITH A

TROUGH EXTENDING SW TO NEAR 10N55W. VERY DRY AIR IS OVER THE

TROPICAL NORTH ATLC UNDER THE INFLUENCE OF THIS TROUGH. A JET

STREAM BRANCH LIES SOUTH AND E OF THE LOW/TROUGH ADVECTING A

PLUME OF MOISTURE NWD OVER THE CENTRAL ATLC BEYOND 31N41W. AT

THE SURFACE...A COUPLE OF WEAK TROUGHS ARE OVER THE W ATLC. THE

FIRST ONE...IS A REFLECTION OF THE UPPER LOW OVER THE CENTRAL

BAHAMAS AND LIES ALONG 76W/77W. THE SECOND ONE IS AN EXTENSION

OF A STATIONARY FRONT AND GOES FROM 31N60W TO 28N65W. SCATTERED

SHOWERS AND ISOLATED TSTMS ARE ASSOCIATED WITH THIS TROUGH. THE

REMAINDER OF THE FORECAST AREA IS UNDER THE INFLUENCE OF THE

AZORES HIGH WHICH IS CENTERED NEAR 36N38W. THIS FEATURE IS

PRODUCING MOSTLY FAIR WEATHER AND MODERATE TRADE WINDS UP TO 20

KT ACROSS THE EAST AND CENTRAL ATLC.

[Iceberg]

Might as well say the same think I did previously.

"Still very little going on, a couple of weak and not very interesting Waves exist.

The main driver for the lack of activity seems to be the still very southerly ITCZ caused in part by the none migration of the Azores High yet ( and no summer for us to as a consequence).

The southerly ITCZ largely prevents any LLCC from occuring in any active waves, Convection is seemly being quashed by persistantly high pressure.

In essence it looks like when our summer starts so will the Hurricane season.

Oh hum...... "

A very quiet start.

[pottyprof]

Kold. Do you think that we could be seeing a second season with very little activity on the hurricane front? It is looking very quiet for the short term. Any ideas mate??

[Somerset Squall]

There's still time, to be honest now usually isn't a particularly active period for atlantic hurricanes anyway but the southerly ITCZ certainly doesn't help as you said.